# Objective
Issue #10243: rendering multiple triangles in the same place results in
flickering.
## Solution
Considered these alternatives:
- `depth_bias` may not work, because of high number of entities, so
creating a material per entity is practically not possible
- rendering at slightly different positions does not work, because when
camera is far, float rounding causes the same issues (edit: assuming we
have to use the same `depth_bias`)
- considered implementing deterministic operation like
`query.par_iter().flat_map(...).collect()` to be used in
`check_visibility` system (which would solve the issue since query is
deterministic), and could not figure out how to make it as cheap as
current approach with thread-local collectors (#11249)
So adding an option to sort entities after `check_visibility` system
run.
Should not be too bad, because after visibility check, only a handful
entities remain.
This is probably not the only source of non-determinism in Bevy, but
this is one I could find so far. At least it fixes the repro example.
## Changelog
- `DeterministicRenderingConfig` option to enable deterministic
rendering
## Test
<img width="1392" alt="image"
src="https://github.com/bevyengine/bevy/assets/28969/c735bce1-3a71-44cd-8677-c19f6c0ee6bd">
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Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
06bf928927